Making Objects Invisible: It's getting easier

Theorists predict a new class of materials that could render objects invisible. The materials work because they interact with light in unusual ways. Researchers are beginning to put those theories into practice, making rudimentary invisibility cloaks by controlling the micro- and nanostructure of materials.To become invisible, an object must do two things: it has to be able to bend light around itself, so that it casts no shadow, and it must produce no reflection. While naturally occurring materials are unable to do this, a new class of materials called metamaterials is now making it easier to render objects invisible.Via MIT Techreview.